Among air experts, it's an open secret: federal and state officials grossly undercount a crucial type of air pollution, often by an order of magnitude and particularly in areas like Houston with its major concentrations of petrochemical plants.

The undercounted pollutants are volatile organic compounds, a type of hydrocarbon that's a major contributor to harmful air.

But at the University of Houston this spring, a much anticipated shipment of advanced air pollution measuring tools from Sweden will arrive at Science and Research Building 1, part of a trans-Atlantic effort by scientists and engineers to address the undercount.

The equipment, including a delicate solar infrared device, will be mounted into a $100,000 Chevy Silverado equipped with amped up cooling and air ride shocks.

UH atmospheric chemist Barry Lefer and Johan Mellqvist of the Swedish company FluxSense then will spend part of the summer driving it down the Ship Channel to Baytown and back, around Texas City and Mont Belvieu, measuring the gases that are emitted by refineries, chemical plants, barges and vehicles.

Integral to the cadre of scientists and engineers concerned about undercounts is Alex Cuclis, an air pollution researcher with the Houston Advanced Research Center. He's also determined to broaden the use of advanced instruments to measure rather than estimate emissions.

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Measuring air pollutants

Both of these devices record results in pounds per hour of emissions.

1 Solar Occultation Flux: Uses the sun's light guided to a detector in a moving vehicle. Pollutants block certain wavelengths and those changes in light are used to fingerprint the pollutants and their concentrations.

1 Differential Absorption Lidar: Uses high powered lasers to create a concentration map, like a cat scan, that visualizes pollutants in a vertical plane. Wind speed is used to calculate the amount of pollutants passing through space.

These volatile vapors are a menace due to how they behave. Like ninth-graders home alone after school, they can get into trouble, congregating with other sketchy gases, causing them to lose oxygens. These free oxygens then hook up with plain oxygen in the bright of day and turn into something else: corrosive ozone, damaging to moist respiratory tissues.

Research on ozone has demonstrated a cruel reality. Healthy children who are active, playing sports in high ozone areas, are more likely to get asthma. Houston decreased its number of harmful ozone days radically, but one out of every nine days in 2010 and 2011 was still bad, Lefer said.

Estimating emissions

Ever since the dawn of the nation's Clean Air Act, the Environmental Protection Agency has provided a method for industrial facilities to estimate emissions of volatile organic compounds. Simplified, "if you refine X barrels of oil, you use this factor to determine how much benzene or formaldehyde is coming from the refinery," Lefer said.

This alone could lead to an undercount. But additionally, many industrial structures are hard to monitor. Imagine the seal around a 300-foot diameter tank, or flanges, or tankers in the Ship Channel with a hatch stuck open. From each of these, gases have been found to escape uncounted.

Each time experts measure with advanced technology, they discover emissions much higher than what is reported to the government.

"We can drive by and see what is coming out of the stacks," Lefer said. "We know how many molecules there are of ethane, of propylene."

Low official numbers

That the estimating system is antiquated is widely acknowledged.

"Consistently, test after test, whether in Port Arthur, Longview, Texas City or the Ship Channel, the emissions estimates are always off by a factor of at least eight," Cuclis said.

Last year an advanced survey in Beaumont-Port Arthur, funded by the Air Quality Research Program, an effort of the University of Texas and Texas Commission on Environmental Quality, documented volatile emissions of the family known as alkanes at 14,700 pounds per hour coming from a group of seven plants. Consider that the Texas Commission on Environmental Quality reported roughly 1,000 tons per day for the entire Houston air basin.

Even the EPA concedes advanced techniques do work. Nevertheless, neither the Texas Commission on Environmental Quality nor the EPA require advanced monitoring techniques. EPA officials declined to be interviewed but said the agency is looking into advanced measurement as it drafts future rules.

In 2007, Brenda Shine wrote in an EPA technical paper that despite limitations, sophisticated laser techniques are "able to accurately quantify the amount of volatile organic compound emissions occurring at the time of measurement."

In Port Arthur last year, a survey detected 418 pounds per hour discharge of the chemical butadiene, a carcinogen used to make synthetic rubber, coming from one source. The facility was supposed to be emitting 2 pounds per hour. So the plant was emitting at least 200 times what it reported, at least when the monitoring truck passed by.

Actual measurements conducted over the past decade in Pasadena, Deer Park, Battleground and Baytown all show equipment giving off amounts that dwarf official emissions numbers.

In July 2008, Houston Mayor Bill White begged the EPA to modernize its estimating system because emissions from Houston refineries and other plants were being underreported by a factor of 100.

The General Accounting Office, a federal oversight agency, in 2001 said the EPA needed to improve oversight of emissions reporting by large facilities.

If officials don't know how much of these gases escape into the blue, they can't pick the best way to reduce ozone smog.

"It is really hard to predict how much anything will affect anything else if our modeling is that far off," Cuclis said.

David Brymer, chief of the air quality division of the Texas Commission on Environmental Quality, agrees there is underreporting. That's why, he said, the state paid to bring modern measurement to Texas several times. The commission also increased its own estimates.

Some companies have brought in advanced measuring tools on their own to see plumes they might miss because many gases are colorless and released high in the air.

Reactions vary

One tool widely used is the infrared camera. It may be used by someone without a Ph.D. at a fraction of the cost of laser technology, but is not as sensitive. Some companies have gone further. LyondellBasell Houston Refinery paid for a survey using advanced tools and, at a conference in Denver recently, encouraged other companies to do the same.

"We would support them being required if it's in lieu of having to go to each valve and do measurements," he said.

Not all companies are eager to bring tools inside the fence line where they might find a bad tank. "Not everyone wants $30 million worth of bad news," said Steve Ramsey, an environmental engineer with the consulting firm ENVIRON, who hopes to bring a laser unit to Houston permanently and hire it out.

Matthew Tejada of Air Alliance Houston had hoped the EPA would begin to require measurements when it rewrote regulations recently.

"We would have finally gotten rid of the slide rule," he said, "it would have been the biggest step taken in this industry since the passage of the Clean Air Act."